Marshfield: James B. Conroy discusses “Our One Common Country: Abraham Lincoln and the Hampton Roads Peace Conference of 1865,” which failed to end the fighting in the War between the states. Book signing follows the lecture. Tuesday, Aug. 26, 10:30 a.m. $5. 1699 Historic Winslow House, 634 Careswell St. 781-837-5753, www.winslowhouse.org